New category: coupon codes

I post lots and lots of coupon codes on this site (especially at this time of year). So … I’m adding a category. Any time I post a code for money off, free shipping, etc. I’ll file it under “coupon code” (as well as “shopping” and “sales.”)

This should make it easier for readers who come here to OTE just for that kind of information to find what they’re looking for.